Well you want to perform "important gigs" opting for the cheapest adapters on the market. (seems like a common idea in this forum, not just yours)
"Open DMX" adapters are suitable for a party with friends, not for a professional service. Search this forum for "open dmx" and see what happens with those adapters.
I normaly would say "go for a PRO device", but if I really have to decide (gun on my head), I'd say Enttec Open might be it.
Don't tell me I haven't warned you

If you want the most stable and most compatible, choose enttec open dmx ethernet or dmxking edmx or similar artnet/sacn node. Tcp/ip drivers are in all systems, and you can even use cat5 cables or wifi if needed. Buy once cry once